GG3 Antibody
Description
Introduction to GG3 Antibody
GG3 is a murine monoclonal antibody specifically targeting the stalk region of influenza hemagglutinin (HA), a key component of the influenza virus. It has been utilized in competitive ELISA (enzyme-linked immunosorbent assay) studies to detect cross-reactive, heterosubtypic neutralizing antibodies (nAbs) in human sera, particularly in the context of H7N9 infection .
Molecular and Functional Characteristics
Key features of GG3:
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Target specificity: Binds to conserved epitopes in the HA stalk region, distinguishing it from head-specific antibodies .
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Mechanism of action: Competes with serum antibodies for HA binding, enabling quantification of stalk-specific immune responses .
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Application: Used to confirm cross-group reactivity (e.g., between H1 and H5 subtypes) in post-infection sera .
Role in Influenza Immunology
GG3 has been instrumental in demonstrating that cross-reactive stalk-specific antibodies are predominantly elicited during infections like H7N9, rather than head-specific responses. For example:
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Early-stage inhibition: Preincubation of HA with GG3 reduced binding activity in sera from H7N9-infected individuals, with peak inhibition observed during the early phase of infection .
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Memory response: The inhibition effect plateaued in later stages, suggesting memory B-cell responses targeting the HA stalk .
| Parameter | Early Infection | Late Infection | Control Group |
|---|---|---|---|
| GG3-mediated inhibition | Significant reduction in binding activity | Reduced inhibition | Baseline levels |
| Source |
Clinical and Diagnostic Implications
GG3’s ability to distinguish stalk-specific antibodies highlights its potential in:
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Vaccine development: Identifying immunogens that induce broad heterosubtypic immunity .
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Biomarker identification: Assessing cross-reactive antibody responses in individuals exposed to diverse influenza strains .
Limitations and Future Directions
While GG3 has proven valuable in mapping HA stalk-specific responses, its utility is constrained by:
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Limited structural data: Detailed epitope mapping and binding kinetics remain uncharacterized.
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Species specificity: As a murine antibody, its relevance to human therapeutic applications is unexplored.
Product Specs
**Constituents:** 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- AGG3, a class C Ggamma subunit in Arabidopsis, possesses a functional transmembrane domain, which is sufficient but not essential for plasma membrane localization. Furthermore, the cysteine-rich C-terminus is located extracellularly. PMID: 25430066
- AGG3 is implicated in the regulation of stomatal aperture by abscisic acid, as well as in developmental processes. PMID: 21575088
